Drop pit mechanism



July 12, 1932. H. K. CHRISTIE 1,866,798

' DROP PIT MECHANISM Filed Aug. 1'7, 1931 2 Sheets-Sheet 1 w\\\ IQ Y SiQ. w 5| MFV Rum m O 3 ---IlHHHHWHHHHINM fN NMX rM| IU Unllmwn|il uk WMVKN. Nm... N.%`\mvmu%` /mnw ummm -,Www N @Nl m. m Nm. hrlumlwww Nm i, 1mf D wmw wywM/MN uw. Nm. NQ .wwf fw um, @w J/ww .wm ww July 12, 1932. H.K, CHRIS-11E DROP PIT MECHANI SM Patented J'uly 12, 1932 narran staresPATENT OFFICE HUGH K. CHRISTIE, OF HARVEY, ILLINOIS, ASSIGNOR TWI'II'IING CORPORATION, OF HARVEY, ILLINOIS, A CORPORATION OF ILLINOISDROP PIT MECHANISM Application filed August 17, 1931.

In the use of drop pit mechanism for removing and replacing locomotiveor other vehicle wheels of the type exemplified in reissue Patent No.17,116, it has been found desirable to simultaneously transport a pairof drop-tables, superimposed one upon the other, so that the lower tablewill be immediately available to replace the table carrying theuncoupled wheels, and to provide workroom in making repairs to thelocomotive or to bridge the pit so that the locomotive with one pair ofwheels removed can be driven off the pit. `When a table is kept underthe locomotive from which the wheels have been removed, it is necessaryto first remove the drop-table under the locomotive, so it can bereplaced by the table, carrying the repaired wheels, and the wheels canbe brought into position to be coupled to the locomotive. Bysuperimposing a pair of tables, the removal and replacing operations areexpedited, because it is not necessary, in replacing the wheels, totransport the table under the locomotive to another track or remove itfrom the truck before the table carrying the repaired wheels istransported to the locomotive. Nor is it necessary to go after anothertable from another track, after the table carrying a pair of wheelsremoved from the locomotive has been disposed of before placing theempty table under the locomotive from which the wheels have beenremoved. In the use of two superimposed tables, it is also advantageousto support one directlyupon the other to avoid substantial increase inthe depth of the pit for the necessary clearances. It has also beenfound necessary to provide means for interlocking the tables againstlateral displacement so they can be conjointly transported by the truckor trolley carrying the raising and lowering mechanism.

The object of the invention is to provide improved drop pit mechanismwhich comprises tables which can be superimposed directly one upon theother, and in close relation, so as to avoid excessive increase in thedepth of the pit, necessary for raising and lowering` of the tables andwheels carried Jthereby. Another object is to provide eflicient meansfor preventing lateral displace- Serial No. 557,551.

ment of the superimposed table so the tables can be conjointlytransported in the pit and raised or lowered.

Another object is to provide means for insuring true vertical alignmentof the superimposed tables to facilitate the iaising and lowering` ofthe superimposed table into pitbridging position. Other objects of theinvention will appear from the description.

The invention consists in the several novel features hereinafter setforth and more particularly defined by claims at the conclusion hereof.

In the drawings: Fig. 1 is a section taken longitudinally through thedrop pit, illustrating mechanism embodying the invention. Fig. 2 is asection taken transversely through the pit. 3 is a perspectiveillustrating the interlocking devices between superimposed tables.

In the modification of the invention illustrated, the pit 10 extendstransversely of and intersects a plurality or series of tracks formed ofrails 12 on the floor of the round house orrepair shop, as wellunderstood in the art. The tracks are interrupted at the pit and adaptedto be bridged by the drop tables hereinafter described.

A wheeled truck or trolley 13 of suitable construction is adapted to runon rails 14 on the bottom of the pit to transport the drop tables fromone track to another, and is equipped with mechanism for raising andlowering the tables so the latter may be raised and locked inpit-bridging position and lowered with a load or pair of wheels thereonto clear the locomotive or tables in operative position at other tracks`at the top of the pit. The lifting mechanism is adapted to separablyengage the tables so it may be lowered to clear them after the tableshave been locked in their pit-bridging position. This lifting mechanismmay consist of four standards 15 having their lower ends fixed in theframe of truck 12, a carriage 16 which is movable vertically on thestandards, and carries a locomotive motor 17 and gearing for drivingworm gears in housings 18 which are screwthreaded to the standards, andare adapted by rotation in opposite directions to raise or titi lowerthe carriage. This raising and lowering mechanism may be, and as shownis, of the construction more fully illustrated in reissue Patent No.17,116. The lifting carriage 16 comprises a frame composed of a spacedpair of girders 19 at either side, housings 18 and cross-members 20, allsecured together to form a rigid construction.

A drop table 21 is provided for each track to bridge the top of the pit.Each table comprises a pair of beams 22 at either side, two pairs ofgirders 23 extending crosswise of beams 22 and end beams 24, all rigidlysecured together. Each pair of girders 23 has fixed thereon a plate 24which carries a railsection 25. These rail-sections 25 are adapted tobridge the space between the ends of rails 12 of the tracks on the floor11. Side platforms 26 are provided on the girders 23 and beams 24, and afloor 27 is laid on beams 22 between the inside girders 23. Each tableis equipped with a set of four horizontally slidable bolts 28 which areadapted to enter sockets 29 in the sides of the pits to support thetable in pit-bridging position. The entire set of bolts is adapted to beshifted by a lever 30 fixed on a. cross-shaft 31 which is journalled inbearings on the table and arms 32 which are connected by links 33 to thebolts respectively, as more fully set forth in reissue Pat ent No.17,116. A lever 30a is fixed to shaft 31 to rock the shaft, andconjointly operate arms 32 to shift the bolts 28. Said bolts areslidably mounted in blocks 34 rigidly secured between the girders 23.When these bolts are retracted into blocks 30, the table will bereleased so it can be supported on the truck and raised or lowered andtransported in the p Each pair of beams 22 of each table is adapted tointerlit with one spaced pair of girders 19 on carriage 16 to preventlateral displacement of the table longitudinally while it is supportedo-n the carriage 16. Guide plates are secured to the carriage 16 toengage the girders 23 and hold the table against transverse displacementon the carriage 16.

Each table is provided adjacent its bottom with four shoes or deviceswhich consist of bent bars bolted to the inner faces of, and projectingbelow, the beams 22, and with four correspondingly arranged lugs 37which are secured to the plates 24 inwardly of the rail sections 25.The'shoes 36 on one table are adapted to engage the lugs 37 on asub'jacent table to lock the superimposed table against lateraldisplacement longitudinally of the rail sections 25 relatively to thelower table. The lower ends of shoes 36 are curved outwardly to guidethe upper table into engagement with lugs 37 when the table on thecarriage is raised into position to engage a table locked inpit-bridging position. The inner edges 36L of shoes 36 are adapted toengage the sides of the heads of rail-sections 25 to lock or secure theupper table against lateral movement transversely of the rail sections25 and relatively to the subjacent table. The lower ends of edges 36aare curved to guide the tables into vertical alignment as they arebrought together. The lower beams 22 of each table are adapted to restdirectly on the rail sections 25 of a subjacent table, so the tableswill pass into close vertical relation, and to avoid excessive depth ofthe pit, to provide the necessary clearance for the movements of thetable and the load thereon in raising and lowering the tables andtransporting them in t-he pit. These shoes and lugs exemplify means forsecuring a plurality of tables directly superimposed one on the otheragainst lateral displacement in all directions so they can be conjointlyraised, lowered, and transported in the pit while the lower table issupported by the lifting mechanism on the truck or trolley. rPhe tablesare constructed so that the upper table will rest and be supported onthe rail sections on the lower table, and resultantly the upper tablewill be solidly supported and held against displacement on the lowertable which is held on the lifting carriage 16.

In the operation, when a pair of wheels is to be uncoupled from alocomotive over the pit, one table thereon will be positioned and lockedin the pit under the wheels of the locomotive rest. The truck, withanother drop table thereon, will then be brought into position beneaththe locked table at the top of the pit. The lifting mechanism will thenbe operated to raise the table on the carriage 16 so it will interlockwith the table in the pit-bridging position, and will lift the uppertable sufficiently to permit the bolts 28 to be retracted and to liftthe wheels so they can be uneoupled from the locomotive. As the tables,during this lifting movement, pass into engaging relation, the shoes 36on the upper table and the lugs 37 on the lower table will be broughttogether, and shoes 36 on the upper table will engage the rail sections25 on the lower table, so the upper table will be locked against lateraldisplacement in any direction relatively to the lower table. The beams22 of the upper table will rest on the railsections 25 of the lowertable, so the upper table will be solidly supported by the rigidframework of the lower table and so these tables will be in closevertical relation. Next, the lifting mechanism will be operated to lowerboth tables together and the wheels on the upper table sufficiently toclear the locomotive. The truck will then be operated to transfer thetables and load to a vacant track. rlhe lifting mechanism will then beoperated to bring the upper table into pitbridging position where itwill be locked so the wheels thereon can be removed to the repair shop.The carriage 16 will then be s the wheels have been removed. Then thelifting mechanism will be operated to bring the table into pit-bridgingposition where it will be locked to provide a work-space under thelocomotive or to permit the locomotiveto be run oil, if desired. Whenthe wheels are ready for replacement, the truck and lifting mechanismare operated to pic-k up the table under the locomotive. The trucl isthen transported to the table having the wheels thereon in an adjacenttrack. 'Ihe latter table is then superimposed on the table on thecarriage 16 and transported across the pit and into position directlyunder the locomotive. Both of the tables are then raised so the wheelson the upper table will be shifted into position for replacement on thelocomotive. Then the superimposed table is locked in place so thelocomotive can be run oli' the single pit.

The invention exemplifies improved drop pit mechanism which is adaptedto handle a plurality of drop tables in close vertical and superimposedrelation; in which simple and eiiicient devices are provided forinterlocking` the tables to prevent relative lateral displacement, inwhich one table is adapted to be supported directly on the rails of asubjacent table; and by which the placement and removal of the tableswill be greatly expedited.

The invention is not to be understood as restricted to the details setforth, since these may be modied within the scope of the appendedclaims, without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire tosecure by Letters Patent, is:

l. In equipment of the character described, the combination with a pit,of a plurality of drop tables, each adapted to bridge und to be loweredin the pit, means for securing the tables in pit-bridging position, andmechanism in the pit for raising and lowering the tables and separablefrom the tables, the tables being adapted to be superimposed one uponthe other in close relation, and provided with interengaging means forpreventing lateral displacement of one table while it is superimposed onthe other, when the tables are in close relation.

2. In equipment of the character described, the combination with a pit,of a plurality of drop tables, each adapted to bridge and to be loweredin the pit, means for securing the tables in pit-bridging position, andmechanism in the pit for raising and lowering the tables and separablefrom the tables, the tables being adapted to be superimposed one uponthe other in close relation, and provided with interengaging means forguiding one table into vertical alignment with the other as they passinto close relation.

3. In equipment of the character described, the combination with a pit,of a plurality of drop tables, each adapted to bridge and to be loweredin the pit, means for securing the tables in pit-bridging position, andmechanism in the pit for raising and lowering the tables and separablefrom the tables, said tables being adapted to be superimposed one uponthe other in close relation, and provided with means for preventingrelative lateral displacement of one table relatively to the other whilethey are in, and for guiding the tables into vertical alignment as theypass into, close relation.v

t. In equipment of the character described, the combination with a pit,of a plurality of drop tables, each adapted to bridge and to be loweredin the pit, means for securing the tables in pit-bridging position, andmechanism in the pit for raising and lowering the tables and separablefrom the tables, said tables being adapted to be superimposed one uponthe other in close relation, and carrying elements iiXed on the tablesadapted to interengage and hold the superimposed table on the subjacenttable.

5. In equipment of the character described, the combination with a pit,of a plurality of drop tables, each adapted to bridge and to be loweredin the pit, means for securing the tables in pit-bridging position, andmechanism in the pit for raising and lowering the tables and separablefrom the tables, said tables being adapted to be superimposed one uponthe other in close relation, and carrying elements fixed on the tablesadapted to interengage and guide the tables into vertical alignment asthey pass into close relation.

6. In equipment of the character described, t-he combination with a pit,of a plurality of drop tables, each adapted to bridge and to be loweredin the pit, means for securing the tables in pit-bridging position, andmechanism in the pit for raising and lowering the tables and separablefrom the tables, said tables being adapted to be superimposed one uponthe other in close relation and guided into vertical alignment andsecured against relative lateral displacement.

7. In equipment of the character described, the combination with a pit,of a` plurality of drop tables, each adapted to bridge and to be loweredin the pit and provided with rails, means for securing the tables inpit-bridging position, and mechanism in the pit for raising and loweringthe tables, and separable therefrom, one table being adapted to besupported on the rails of another table, the table being provided withmeans for securing a superimposed table against lateral displacement,while it is supported on the rails of a subjacent table.

8. In equipment of the character described,

the combination with a pit, of a plurality of drop tables, each adaptedto bridge and to be lowered in the pit and provided with rails, meansfor securing the tables in pit bridging position, and mechanism in thepit for raising and lowering the tables, and separable therefrom, thetables being adapted to be supported on the rails of another table, thetables being provided with means for guiding them into verticalalignment as they pass into close relation.

9. In equipment of the character described, the combination with a pit,of a plurality of drop tables, each adapted to bridge and to be loweredin the pit and provided with rails, means for securing the tables inpit-bridging position, and mechanism in the pit for raising and loweringthe tables, and separable therefrom, one table being adapted to besupported on the rails of another table, the tables being provided withmeans for guiding them into vertical alignment as they pass into, andsecuring the superimposed table against lateral displacement while in,close relation.

10. In equipment of the character described, the combination with a pit,of a plurality of drop tables, each adapted to bridge, and to be loweredin, the pit, means tor securing the tables in pit-bridging position, andmechanism in the pit for raising and lowering thetables and separablefrom the tables, the tables being adapted to be superimposed one uponthe other in close relation, and provided with inter-engaging devicesxedly secured on the tables for holding a superimposed table.

11. In equipment of the character described, the combination with a pit,of a plurality of drop tables, each adapted to bridge and to be loweredin the pit, means for securing the tables in pit-bridging position, andmechanism in the pit for raising and lowering the tables and separablefrom the tables, the tables being adapted to be superimposed one uponthe other in close relation, and provided with devices iXedly secured onthe tables, and for guiding a superimposed table into vertical alignmentwith a subjacent table.

12. In equipment of the character de! scribed, the combination with apit, of aplurality of drop tables, each adapted to bridge and to belowered in the pit, means for securing the tables in pit-bridgingposition, and mechanism in the pit for raising and lowering the tablesand separable from the tables, the tables being adapted to besuperimposed one upon the other in close relation, and provided withdevices fixedly secured on the tables for guiding them into verticalalignment and preventing lateral displacement of the superimposed table.

13. In equipment of the character described, the combination with a pit,of a plurality of drop tables, each adapted to bridge and to be loweredin the pit, means for securing the tables in pit-bridging position, andmechanism in the pit for raising and lowering the tables and separablefrom the tables, the tables being adapted to be superimposed one uponthe other in close relation and provided with lixed shoes to engage asubjacent table and hold the superimposed table thereon.

14. In equipment of the character described, the combination with a pit,of a plurality of drop tables each adapted to bridge and to be loweredin the pit and provided with rails, means for securing the tables inpit-bridging position, mechanism in the pit for raising and lowering thetables, and separable therefrom, one of the tables being adapted to besupported on the rails of the other tab-le, and provided with fixedshoes to engage the rails of a subj acent table.

15. In equipment of the character described, the combination with a pit,of a plurality of drop tables, each adapted to bridge and to be loweredin the pit, means for securing the tables in pit-bridging position, andmechanism in the pit for raising and lowering the tables and separablefrom the tables, the tables being adapted to be superimposed one uponthe other in close relation and provided with fixed shoes to engage asubjacent table and hold the superimposed table thereon and with Xedlugs for engagement with the shoes of the superimposed table.l

Signed at Harvey, Illinois, this 4th day of August, 1931.

HUGH K. CHRISTIE.

